A device and a method for controlling the temperature of a component in a printing press are known from DE 44 29 520 A1. The component is temperature controlled by the use of an at least partially circulating fluid. A control element, with which a mixing ratio can be adjusted at an intake point for two fluid streams having different temperatures, is controlled through a temperature measuring site that is located between the intake point for the fluid streams and the component itself.
EP 08 86 577 B1 discloses a device and a method for controlling the temperature of a component. A component temperature is monitored via sensors, and the measured value is provided to a control unit. If the temperature measured at the component deviates from a target value, the control unit will decrease or will increase the temperature of a cooling medium in a cooling unit by a certain amount and wait for a defined period of time. It will then repeat the measurement and the listed steps until the target value is reached again.
EP 03 83 295 A2 discloses a temperature controlling device for printing presses. A temperature of the fluid in an intake line and a surface temperature of the component to be temperature controlled are detected and these temperatures are supplied to a control device. Based upon these temperatures, and, if applicable, also based upon prescribed influencing parameters, such as the paper that is used, the ratio of wetting agent, and target temperatures, for example, a control variable, which is usable for controlling a mixing motor, is determined. This control variable adjusts the ratio between circulating fluid and freshly supplied temperature controlled fluid.
JP 60-161152 A discloses a cooling device of a roller to be temperature controlled. A surface temperature of the roller and a fluid temperature in the inflow path are measured. These values are supplied to a control device for comparison with a target value and for use in controlling a valve.
In WO 2004/054805 A1, a measured temperature, which at least approximately represents the temperature of the component, and especially in the case of a roller, a temperature that represents the surface temperature of the roller, is adjusted to, and/or is maintained at a certain target value through temperature control via a temperature control device. This is carried out using a cascade-type controller structure. Elements of the control or path model are provided in the closed loops.
From WO 03/045695 A1, it is known that for different production speeds, different target temperature values or different maximum values can be prescribed.
DE 10 2005 005 303 A1 relates to a system for controlling the temperature of components of a printing press. It is proposed, among other things, that an intended change in the press speed can be delayed in its execution, such as, for example, by appropriate programming in an evaluation unit, until a certain temperature is reached on the roller.
In DE 10 2004 006 231 B3 a method of transporting dampening agent from a first roller to a forme cylinder is known.
Roller surface temperatures can be controlled only very slowly, in comparison with the ability to control the rotational speed of a press. Therefore, despite various precontrol and derivative action measures, with faster changes taking place in rotational speed, temperatures can lag behind to a greater or lesser extent. In terms of interface technology, temperature control has heretofore been based upon the current rotational press speed, and will therefore attempt to adapt the temperature to it. Ink densities during transient operating phases, such as, for example, during run-up and cool-down phases, therefore may not remain constant enough, or rotational speed may be changed only extremely slowly.